1a. Objectives (from AD-416)
Objective 1: Strategically expand the genetic diversity in genebank collections and improve associated information for priority cool season food and forage legume, turf and forage grass, native rangeland, oilseed, vegetable, medicinal, ornamental, and other specialty and industrial crop genetic resources. Objective 2: Conserve and regenerate priority cool season food and forage legume, turf and forage grass, native rangeland, oilseed, vegetable, medicinal, ornamental, and other specialty and industrial crop genetic resources efficiently and effectively, and distribute samples and associated information worldwide. Objective 3: Strategically characterize (“genotype”) and evaluate (“phenotype”) crop core subsets and other priority germplasm for molecular markers, morphological descriptors, and key agronomic or horticultural traits, such as general adaptation, phenology, and growth potential. Objective 4: Develop genetically-enhanced populations of priority crops to broaden the genetic base of breeding genepools.
1b. Approach (from AD-416)
Plan and conduct both traditional as well as new and innovative activities to acquire, store, regenerate, evaluate/characterize, and distribute plant germplasm assigned to this project. Also, develop new conservation and preservation protocols that enable long-term genetic security. Prepare and publish appropriate articles, peer reviewed manuscripts and Internet (Germplasm Resources Information Network) data sets for the germplasm user community. Conduct research programs on molecular characterization of selected collections; the impact/use of insects as pests, pollinators and/or biological control agents; the interaction of fungi as plant disease organisms or plant mycosymbionts; and the physiological aspects of seed production relative to seed preservation and long-term storage. Replacing 5348-21000-020-00D (3/08).
3. Progress Report
Genetic resources are important to ensure the continued progress in genetic improvement through breeding as well as in plant genomics research. During 2008, three successful collection trips to four countries by the WRPIS scientists brought in approximately 2,000 accessions of various species to the WRPIS. As of August 2, 2008, the total holdings reached 79,014 accessions belonging to 2,700 plant species. A total of 21,532 seed packets were distributed to 564 requesters worldwide last year, indicating significant interest in using WRPIS germplasm. (NP 301, Component 1. Phenotypic data and molecular genotype data add value to the accessions in the collection and promote the use of the germplasm. In FY 2008, we contributed to the GRIN database 35,763 observation records for 151 descriptors of 21 crops. Six percent of these data points were from our collaborators. We completed seed increase for 2833 accessions from a broad range of plant species. A small proportion of our bean collection had low germination percentage due to many years in the storage or poor seed quality of the original seed sources. We are actively searching for a better growth media for regenerating there accessions. Through testing various medium reported in the literature, we have identified one promising medium which substantially improved the germination percentage. Our molecular lab genotyped the pea core collection with microsatellite markers at 20 loci, analyzed the population structure of 96 bulked Indian ricegrass field samples with AFLP markers and assessed the population diversity of the Taper-tip onion collection. We also completed an AFLP analysis of eight populations of smooth brome and initiated the development of procedures to identify duplicate accession in the cool-season grass collection. In FY 2008, our agronomist selected 55 promising populations of blue wildrye grass collected in the Blue Mountains of Oregon and Washington as the genetic resources of key native species for revegetation on public lands. We released the first three winter hardy safflower germplasm lines to meet the need of these stakeholders interested in developing an alternative broadleaf rotation crop with wheat in dry areas. Our Plant Pathologist, in collaboration with others, delineated phylogenetic relationships within seed-associated pathogens, the Alternaria infectoria complex; clarified nomenclature for 750+ species in the genus Cladosporium (many species are seed-associated opportunistic pathogens); first reported on Fusarium proliferatum (a mycotoxigenic fungus) in garlic in North America, and documented F. proliferatum and other pathogens as widespread in commercially distributed seed garlic; and documented the leaf surface as a site for sporulation of the Neotyphodium endophyte of Poa ampla. Our entomologist completed a study on the inheritance of pea weevil resistance in interspecific crosses, research on pod-boring Lepidoptera resistance in chickpea recombinant inbred lines, and demonstrated the retention of viable Neotyphodium fungal endophytes during seed regeneration of tall fescue accessions at the Pullman PI Station.
1. Identifying and preserving microbial germplasm (Neotyphodium endophytic fungi) in temperate grasses. Sources of Neotyphodium endophyte strains are needed for the commercial development of new grass-endophyte associations by public and private sector scientists in the U.S. and abroad. A 3-year research project by ARS scientists at the Western Regional Plant Introduction Station (WRPIS) in Pullman, WA demonstrated that diverse endophyte strains have been preserved in regenerated seed of multiple tall fescue accessions stored for prolonged periods of time in the WRPIS seed bank. The potential impact of this research is expanded development of new grass cultivars harboring Neotyphodium strains that do not produce alkaloid toxins that adversely affect grazing cattle and sheep but still produce the necessary metabolites for insect resistance and other ecological benefits. This relates to NP 301, Problem Statement 1A.
2. Winter Safflower and Fall Acclimation Capacity. In many semi-arid regions a winter annual broadleaf is needed in a rotation system with wheat. Fall planted safflower develops earlier has higher yield potential than spring planted safflower. Additional research by ARS scientists in the Plant Germplasm Introduction and Testing Research Unit in Pullman, WA showed that safflower winter hardiness was related to both prostate habit and high winter acclimation capacity in the fall. Thus both of these factors must be considered as winter safflower cultivars are developed. Recent work has led to the release and winter hardy safflower lines that could address the rotation need. This relates to NP 301, Problem Statement 1A.
3. New plant germplasm for producing natural rubber. A source of domestic rubber is needed in order to reduce the dependence on imported rubber. High rubber content is found in the fleshy root of the perennial Russian dandelion, Taraxacum kok-sagyz, native to Kazakhstan. ARS researchers in the Plant Germplasm Introduction and Testing Research Unit in Pullman, WA participated in a successful collection trip in 2008 to Kazakhstan and brought in seed and root pieces from about 20 populations. These new germplasms could be used in research and breeding programs to develop a domestic source of new rubber. This relates to NP 301, Problem Statement 1A.
4. Breeding for High Water Use Efficiency in Tall Fescue. Tall fescue is grown on more than 14 million hectares in the U.S. but often exposed to summer droughts that reduce forage production. Low carbon isotope discrimination (CID) is associated with high water use efficiency in tall fescue. Research by ARS scientists in the Plant Germplasm Introduction and Testing Research Unit in Pullman, WA showed that CID is heritable and can be used in a breeding program. Selection would be most efficient with one cycle of selection on spaced plants. This research could help to develop Tall Fescue cultivars with improved water-use efficiency. This relates to NP 301, Problem Statement 1A.
5. Genetic Resistance to Fusarium Root Rot in Pea. Legume production, especially of dry pea, has increased dramatically in the northern tier states of North Dakota and Montana. Fusarium root rot is a devastating disease of both vegetable and dry pea production in the USA, especially in summer rainfall areas. The ARS scientists in the Plant Germplasm Introduction and Testing Research Unit in Pullman, WA released and published three new pea germplasms (W6 26740, W6 26743 and W6 26745) with improved agronomic qualities and high levels of resistance to Fusarium root rot for immediate use by breeders for cultivar improvement. This research will help breeders develop pea cultivars resistant to Fusarium root rot. This relates to NP 301, Problem Statement 1A.
6. Investigation of microorganisms in germplasm. Pathogens in germplasm constitute a threat to germplasm health, whereas symbionts constitute opportunities to augment germplasm value. The ARS researchers at the Plant Germplasm Introduction and Testing Research Unit in Pullman, WA found that the results for taxonomy and nomenclature of Alternaria and Cladosporium greatly advanced basic understanding of these exceedingly numerous, cosmopolitan and ubiquitous seed-associated pathogens and saprophytes. Correctly identifying these microorganisms will form the base for developing proper strategies in germplasm management. This relates to NP 301, Problem Statement 1A.
5. Significant Activities that Support Special Target Populations
Garlic is one of the economically important specialty crops. However, garlic production is often small scale on small farms. Our research on garlic pathogens produced identification guides (Compendium of Onion and Garlic Diseases and Pests) with relevance to small production farms.
Du Toit, L.J., Dugan, F.M. 2008. Fusarium bulb rot of onion and garlic, pp.15-17 in: Compendium of Onion and Garlic Diseases and Pests, 2nd ed., edited by H.F. Schwartz and S.K. Mohan. APS Press, St. Paul, MN. Book Chapter.
Tadych, M., Bergen, M., Dugan, F.M., White, J.F. 2007. The potential role of water in spread of conidia of the Neotyphodium endophyte of Poa ampla. Mycological Research. 111: 466-472.
Coyne, C.J., Porter, L., Inglis, D.A., Grunwald, N.J., Mcphee, K.E., Muehlbauer, F.J. 2008. Registration of W6 26740, W6 26743 and W6 26745 Green Pea Germplasm Resistant to Fusarium Root Rot. Journal of Plant Registrations (2008) Vol 2, No. 2, 137-139.
Dugan, F.M., Groenewald, J.Z., Crous, P.W., Braun, U. 2008. Morphological plasticity in Cladosporium sphaerospermum. Persoonia: Molecular Phylogeny and Evolution of Fungi 21:9-16.
Sharma, H.C., Gowda, C.L., Stevenson, P.C., Ridsdill-Smith, T.J., Clement, S.L., Ranga Rao, G.V., Romies, J., Miles, M., Bouhssini, M. 2007. Host Plant Resistance and Insect Pest Management in Chickpea. Chickpea Breeding and Management. In: Yadav S.S., R.J. Redden, W. Chen, B. Sharma, editors. Chickpea Breeding and Management. CAB International, Wallingford, U.K., pp. 520-537.